Self-mixing interferometry of distance at wavelength modulation of semiconductor laser

Theoretical description for method of distance measurement at alteration emission wavelength of semiconductor laser, operated in self-mixing regime, has been presented. The result of computer modeling of self-mixing signal at harmonic wavelength modulation of laser diode has been represented. Spectral harmonic selection of low-frequency spectrum of self-mixing signal for distance measurement has been theoretically substantiated. The results of distance measurements using self-mixing laser interferometer, at deviation of emission frequency, corresponding 0.00046% of laser diode wavelength has been demonstrated.